A preoperative evaluation consists at a minimum of a history and physical exam in the professional’s office. In addition, they may require additional studies such as an electrocardiogram (EKG) or chest x-ray. There may even be more studies required such as a stress test or echocardiogram. It is beyond the scope of this chapter to give the rationale behind each study, but we will deal with these individually in the future on our website. To say the least, the purpose of all these efforts is to identify any problem that might lead to complications and address these before surgery. If a significant problem is identified which cannot be resolved, the surgery may be cancelled.